Question

I calculated 56 travel times from Home to Campus and Campus to Home. My mean time is equal (15 minutes) however, my variance for HOME to CAMPUS is 26.45 and my variance for CAMPUS to HOME is 14.06.

What is the reason that my mean times were equal but my variances were so far apart? How can this data be improved upon?

Answer 1

The mean time from Home to Campus = The mean time from Campus to Home

This indicates that you take on average exactly the same time for going from Home to Campus and for Campus to Home.

But,

The variances were so apart indicates that day to day variation in travel times for Home to Campus is much different from day to day variation in travel times for Campus to Home.

That means, even though on average you take the sam time for both onward and return trip, there is much disparity in the values around the mean. That means you are not consistent.

You can improve the data by being consistent in your timings of day to day for up and down.